Hospital Rounds: News You Can Use in Hospital Pharmacy

APRIL 01, 2002

L. Kendall Shaw, PharmD

Daily Aspirin Doing More Harm Than Good?According to a report by the U.S. Preventive Services Task Force, although daily aspirin intake can reduce the risk of coronary heart disease by up to 28% in patients who have never had a heart attack but who are at increased risk of coronary heart disease, the vast majority of healthy people may not derive such benefit. The increase in incidence of gastrointestinal bleeding and hemorrhagic stroke associated with daily aspirin intake may actually pose a greater risk for patients with low or even average risk of developing coronary heart disease. The Task Force, therefore, recommends that clinicians carefully evaluate cardiovascular risk factors for each patient and counsel on whether or not aspirin?s benefits outweigh its risks. ?For most people, daily aspirin does more harm than good.?Chiropractic Journal March 2002.

MDIs and Holding ChambersA recent study of pulmonary drug delivery used a cascade impactor to determine the amount of drug actually reaching its destination. Doses of Flovent (fluticasone) were actuated without and with an Aerochamber Plus or an EasiVent. Surprisingly, a metered dose inhaler (MDI) delivered 50.3 mcg, which was almost identical to that seen with the Aerochamber Plus (47.9 mcg). The EasiVent delivered only 27 mcg. Of course, these results assume that the patients will always use their MDIs correctly, but holding chambers may actually impair drug delivery in some cases.Ann Allergy Asthma Immunol 2002;88:204-208.

Pneumococcal Resistance to Levofloxacin EmergingFluoroquinolones have been considered to be particularly resistant to resistance development, but a series of recent cases at Mount Sinai Hospital in Toronto, Canada, have shown that Streptococcus pneumoniae has developed resistance to levofloxacin during therapy in severe respiratory infections. Sputum samples taken prior to antibiotic therapy indicated susceptibility to levofloxacin, but subsequent treatment failures, some fatal, indicated resistant strains upon re-evaluation.N Engl J Med 2002;346:722,747-750

ACE Inhibitors and Preserving Physical FunctionA study of almost 650 women with a mean age of 78 were followed over a 3-year period to observe their rate of decline in physical strength. Maximum isometric strength of the knee extensor muscles was measured repeatedly over that time, as was walking speed. Of these patients, 61 were on continuous angiotension-converting enzyme (ACE) inhibitor therapy for the duration of the study, and others began or discontinued use during the 3-year period. Some patients took other antihypertensive agents, and still others had no anti-hypertensive intervention.

Decline in muscle strength among those on continuous ACE inhibitor therapy was 1.0 kg, but 3.0 to 3.9 kg among other patients. Reductions in walking speed among those on continuous ACE inhibitor therapy averaged 1.7 cm/sec and 13.6 to 17.9 cm/sec in the other groups. Researchers caution that further study is warranted before conclusions are drawn, but ACE inhibitors may actually confer more benefit in elderly patients requiring antihypertensive intervention than simply blood pressure control.Lancet 2002;359:926-930

Reducing CMV infection in Lung Transplant PatientsPatients receiving lung transplants and the necessary immunosuppressive therapy to ensure success of that operation are at high risk of cytomegalovirus (CMV) infection and typically have been given early prophylactic regimens of either acyclovir alone or a combination of acyclovir and ganciclovir. A recent study at Vanderbilt University Medical Center in Nashville, TN, however, has demonstrated that initiating ganciclovir prophylaxis 3 to 4 weeks after transplantation actually improves outcomes, reducing rates of CMV infection from 80% with previous regimens to only 48% with delayed therapy, and CMV disease was reduced from 31% to 10% by delayed prophylaxis.Chest 2002;121:407-414.

Homeopathic Immunotherapy for AsthmaA UK study of asthmatics with confirmed asthmatic reaction to dust mites evaluated treatment with placebo or ultramolecular doses of house dust mite prepared in 30 dilutions of 100:1. Comparison of asthma diaries and clinical evaluations revealed essentially no overall difference between the two groups regarding lung function or quality of life, despite the fact that both groups experienced some improvement in symptoms. Patients receiving the homeopathic dilutions, however, exhibited a vacillating pattern of symptom exacerbation and improvement not seen in the placebo group.BMJ 2002;324:520-523.

Allergic Rhinitis and Asthma?Overstating the ObviousA retrospective study of patients between the ages of 12 and 60 years suffering both conditions has concluded that those treated regularly for allergic rhinitis experienced fewer hospital admissions and emergency room visits related to asthma.J Allergy Clin Immunol 2002;109:57-62.

More Detail Revealed In Asthma PathophysiologySeparate studies have verified two very different changes in the normal function of the lungs of asthmatics compared with normal lungs, emphasizing the importance of regular anti-inflammatory intervention to prevent permanent remodeling of lung tissues. The inflammatory response to allergen challenge in patients with asthma causes epithelial cell proliferation and stimulates myofi-broblast collagen production.

Bronchodilation is the normal response to deep inhalation in nonasthmatic individuals; but bronchoconstric-tion is often the response seen in those with asthma. The reasons behind this fundamental and profound difference are undoubtedly complex, but one contributing factor may be edema in bronchial epithelial layers and ensuing reduction of airway perfusion induced by negative intrathoracic pressures. The theory is that rapid deep inspiration creates a pressure gradient across the capillary wall that causes a leaky low-pressure capillary bed in the more vascular asthmatic airway, causing extravasation of fluid into the airway wall, increasing wall thickness, reducing airway lumen size, and thus reducing specific airway conductance.Thorax 2002;57:116-119.Am J Respir Crit Care Med 2002;165:266-272.

Identifying and Treating CFSSevere fatigue, a common complaint, is often transient, but it can be persistent and disabling, indicating the potential presence of chronic fatigue syndrome (CFS). Symptoms of CFS include debilitating fatigue with myalgias, tender lymph nodes, arthralgias, chills, feverish feelings, and postexertional malaise. Diagnosis of this disorder is challenging, because physical examination reveals no abnormalities and there is no definitive laboratory test. The cause of CFS remains unknown, although it is similar to fibromyalgia. Concomitant illnesses typically include irritable bowel syndrome, depression, and headaches. Because identification of the cause of CSF remains elusive, health care practitioners, including pharmacists, should be more attuned to the possible presence of CSF. Treatment varies according to a patient?s presentation and should include exercise, diet, sleep, antidepres-sants, and other medications.Am Fam Physicians 2002;65(6):1083-1090.